Move actual rte selection process from rtalloc_mpath_fib()
to the rt_path_selectrte() function. Add public
rt_mpath_select() to use in fibX_lookup_ functions.
The only piece of information that is required is rt_flags subset.
In particular, if_loop() requires RTF_REJECT and RTF_BLACKHOLE flags
to check if this particular mbuf needs to be dropped (and what
error should be returned).
Note that if_loop() will always return EHOSTUNREACH for "reject" routes
regardless of RTF_HOST flag existence. This is due to upcoming routing
changes where RTF_HOST value won't be available as lookup result.
All other functions require RTF_GATEWAY flag to check if they need
to return EHOSTUNREACH instead of EHOSTDOWN error.
There are 11 places where non-zero 'struct route' is passed to if_output().
For most of the callers (forwarding, bpf, arp) does not care about exact
error value. In fact, the only place where this result is propagated
is ip_output(). (ip6_output() passes NULL route to nd6_output_ifp()).
Given that, add 3 new 'struct route' flags (RT_REJECT, RT_BLACKHOLE and
RT_IS_GW) and inline function (rt_update_ro_flags()) to copy necessary
rte flags to ro_flags. Call this function in ip_output() after looking up/
verifying rte.
Reviewed by: ae
Such handler should pass different set of variables, instead
of directly providing 2 locked route entries.
Given that it hasn't been really used since at least 2012, remove
current code.
Will re-add it after finishing most major routing-related changes.
Discussed with: np
and t_maxseg. This dualism emerged with T/TCP, but was not properly cleaned
up after T/TCP removal. After all permutations over the years the result is
that t_maxopd stores a minimum of peer offered MSS and MTU reduced by minimum
protocol header. And t_maxseg stores (t_maxopd - TCPOLEN_TSTAMP_APPA) if
timestamps are in action, or is equal to t_maxopd otherwise. That's a very
rough estimate of MSS reduced by options length. Throughout the code it
was used in places, where preciseness was not important, like cwnd or
ssthresh calculations.
With this change:
- t_maxopd goes away.
- t_maxseg now stores MSS not adjusted by options.
- new function tcp_maxseg() is provided, that calculates MSS reduced by
options length. The functions gives a better estimate, since it takes
into account SACK state as well.
Reviewed by: jtl
Differential Revision: https://reviews.freebsd.org/D3593
entries data in unified format.
There are control plane functions that require information other than
just next-hop data (e.g. individual rtentry fields like flags or
prefix/mask). Given that the goal is to avoid rte reference/refcounting,
re-use rt_addrinfo structure to store most rte fields. If caller wants
to retrieve key/mask or gateway (which are sockaddrs and are allocated
separately), it needs to provide sufficient-sized sockaddrs structures
w/ ther pointers saved in passed rt_addrinfo.
Convert:
* lltable new records checks (in_lltable_rtcheck(),
nd6_is_new_addr_neighbor().
* rtsock pre-add/change route check.
* IPv6 NS ND-proxy check (RADIX_MPATH code was eliminated because
1) we don't support RTF_ANNOUNCE ND-proxy for networks and there should
not be multiple host routes for such hosts 2) if we have multiple
routes we should inspect them (which is not done). 3) the entire idea
of abusing KRT as storage for ND proxy seems odd. Userland programs
should be used for that purpose).
Add if_requestencap() interface method which is capable of calculating
various link headers for given interface. Right now there is support
for INET/INET6/ARP llheader calculation (IFENCAP_LL type request).
Other types are planned to support more complex calculation
(L2 multipath lagg nexthops, tunnel encap nexthops, etc..).
Reshape 'struct route' to be able to pass additional data (with is length)
to prepend to mbuf.
These two changes permits routing code to pass pre-calculated nexthop data
(like L2 header for route w/gateway) down to the stack eliminating the
need for other lookups. It also brings us closer to more complex scenarios
like transparently handling MPLS nexthops and tunnel interfaces.
Last, but not least, it removes layering violation introduced by flowtable
code (ro_lle) and simplifies handling of existing if_output consumers.
ARP/ND changes:
Make arp/ndp stack pre-calculate link header upon installing/updating lle
record. Interface link address change are handled by re-calculating
headers for all lles based on if_lladdr event. After these changes,
arpresolve()/nd6_resolve() returns full pre-calculated header for
supported interfaces thus simplifying if_output().
Move these lookups to separate ether_resolve_addr() function which ether
returs error or fully-prepared link header. Add <arp|nd6_>resolve_addr()
compat versions to return link addresses instead of pre-calculated data.
BPF changes:
Raw bpf writes occupied _two_ cases: AF_UNSPEC and pseudo_AF_HDRCMPLT.
Despite the naming, both of there have ther header "complete". The only
difference is that interface source mac has to be filled by OS for
AF_UNSPEC (controlled via BIOCGHDRCMPLT). This logic has to stay inside
BPF and not pollute if_output() routines. Convert BPF to pass prepend data
via new 'struct route' mechanism. Note that it does not change
non-optimized if_output(): ro_prepend handling is purely optional.
Side note: hackish pseudo_AF_HDRCMPLT is supported for ethernet and FDDI.
It is not needed for ethernet anymore. The only remaining FDDI user is
dev/pdq mostly untouched since 2007. FDDI support was eliminated from
OpenBSD in 2013 (sys/net/if_fddisubr.c rev 1.65).
Flowtable changes:
Flowtable violates layering by saving (and not correctly managing)
rtes/lles. Instead of passing lle pointer, pass pointer to pre-calculated
header data from that lle.
Differential Revision: https://reviews.freebsd.org/D4102
cperciva's libmd implementation is 5-30% faster
The same was done for SHA256 previously in r263218
cperciva's implementation was lacking SHA-384 which I implemented, validated against OpenSSL and the NIST documentation
Extend sbin/md5 to create sha384(1)
Chase dependancies on sys/crypto/sha2/sha2.{c,h} and replace them with sha512{c.c,.h}
Reviewed by: cperciva, des, delphij
Approved by: secteam, bapt (mentor)
MFC after: 2 weeks
Sponsored by: ScaleEngine Inc.
Differential Revision: https://reviews.freebsd.org/D3929
send_queue and the socket is closed. This results in strange
race conditions for the application.
While there, remove a stray character.
MFC after: 3 days
TFO is disabled by default in the kernel build. See the top comment
in sys/netinet/tcp_fastopen.c for implementation particulars.
Reviewed by: gnn, jch, stas
MFC after: 3 days
Sponsored by: Verisign, Inc.
Differential Revision: https://reviews.freebsd.org/D4350
creation will print extra lines on the console. We are generally not
interested in this (repeated) information for each VNET. Thus only
print it for the default VNET. Virtual interfaces on the base system
will remain printing information, but e.g. each loopback in each vnet
will no longer cause a "bpf attached" line.
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Reviewed by: gnn
Differential Revision: https://reviews.freebsd.org/D4531
on vnet enabled jail shutdown. Call the provided cleanup
routines for IP versions 4 and 6 to plug these leaks.
Sponsored by: The FreeBSD Foundation
MFC atfer: 2 weeks
Reviewed by: gnn
Differential Revision: https://reviews.freebsd.org/D4530
- Use SDT_PROBE<N>() instead of SDT_PROBE(). This has no functional effect
at the moment, but will be needed for some future changes.
- Don't hardcode the module component of the probe identifier. This is
set automatically by the SDT framework.
MFC after: 1 week
If source of ARP request didn't pass the routing check
(e.g. not in directly connected network), be polite and
still answer the request instead of dropping frame.
Reported by: quadro at irc@rusnet
to do is to clean up the timer handling using the async-drain.
Other optimizations may be coming to go with this. Whats here
will allow differnet tcp implementations (one included).
Reviewed by: jtl, hiren, transports
Sponsored by: Netflix Inc.
Differential Revision: D4055
When using lagg failover mode neither Gratuitous ARP (IPv4) or Unsolicited
Neighbour Advertisements (IPv6) are sent to notify other nodes that the
address may have moved.
This results is slow failover, dropped packets and network outages for the
lagg interface when the primary link goes down.
We now use the new if_link_state_change_cond with the force param set to
allow lagg to force through link state changes and hence fire a
ifnet_link_event which are now monitored by rip and nd6.
Upon receiving these events each protocol trigger the relevant
notifications:
* inet4 => Gratuitous ARP
* inet6 => Unsolicited Neighbour Announce
This also fixes the carp IPv6 NA's that stopped working after r251584 which
added the ipv6_route__llma route.
The new behavour can be controlled using the sysctls:
* net.link.ether.inet.arp_on_link
* net.inet6.icmp6.nd6_on_link
Also removed unused param from lagg_port_state and added descriptions for the
sysctls while here.
PR: 156226
MFC after: 1 month
Sponsored by: Multiplay
Differential Revision: https://reviews.freebsd.org/D4111
This routine checks that there are no locks held for an inp,
without having any lock on the inp. This breaks if the inp
goes away when it is called. This happens on stress tests
on a RPi B+.
MFC after: 3 days
ip_dooptions(), icmp6_redirect_input(), in6_lltable_rtcheck(),
in6p_lookup_mcast_ifp() and in6_selecthlim() use new routing api.
Eliminate now-unused ip_rtaddr().
Fix lookup key fib6_lookup_nh_basic() which was lost diring merge.
Make fib6_lookup_nh_basic() and fib6_lookup_nh_extended() always
return IPv6 destination address with embedded scope. Currently
rw_gateway has it scope embedded, do the same for non-gatewayed
destinations.
Sponsored by: Yandex LLC
other end till it reaches predetermined threshold which is 3 for us right now.
Once that happens, we trigger fast-retransmit to do loss recovery.
Main problem with the current implementation is that we don't honor SACK
information well to detect whether an incoming ack is a dupack or not. RFC6675
has latest recommendations for that. According to it, dupack is a segment that
arrives carrying a SACK block that identifies previously unknown information
between snd_una and snd_max even if it carries new data, changes the advertised
window, or moves the cumulative acknowledgment point.
With the prevalence of Selective ACK (SACK) these days, improper handling can
lead to delayed loss recovery.
With the fix, new behavior looks like following:
0) th_ack < snd_una --> ignore
Old acks are ignored.
1) th_ack == snd_una, !sack_changed --> ignore
Acks with SACK enabled but without any new SACK info in them are ignored.
2) th_ack == snd_una, window == old_window --> increment
Increment on a good dupack.
3) th_ack == snd_una, window != old_window, sack_changed --> increment
When SACK enabled, it's okay to have advertized window changed if the ack has
new SACK info.
4) th_ack > snd_una --> reset to 0
Reset to 0 when left edge moves.
5) th_ack > snd_una, sack_changed --> increment
Increment if left edge moves but there is new SACK info.
Here, sack_changed is the indicator that incoming ack has previously unknown
SACK info in it.
Note: This fix is not fully compliant to RFC6675. That may require a few
changes to current implementation in order to keep per-sackhole dupack counter
and change to the way we mark/handle sack holes.
PR: 203663
Reviewed by: jtl
MFC after: 3 weeks
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D4225
Vast majority of rtalloc(9) users require only basic info from
route table (e.g. "does the rtentry interface match with the interface
I have?". "what is the MTU?", "Give me the IPv4 source address to use",
etc..).
Instead of hand-rolling lookups, checking if rtentry is up, valid,
dealing with IPv6 mtu, finding "address" ifp (almost never done right),
provide easy-to-use API hiding all the complexity and returning the
needed info into small on-stack structure.
This change also helps hiding route subsystem internals (locking, direct
rtentry accesses).
Additionaly, using this API improves lookup performance since rtentry is not
locked.
(This is safe, since all the rtentry changes happens under both radix WLOCK
and rtentry WLOCK).
Sponsored by: Yandex LLC
* When processing a cookie, use the number of
streams announced in the INIT-ACK.
* When sending an INIT-ACK for an existing
association, use the value from the association,
not from the end-point.
MFC after: 1 week
LLE structure is mostly unchanged during its lifecycle.
To be more specific, there are 2 things relevant for fast path
lookup code:
1) link-level address change. Since r286722, these updates are performed
under AFDATA WLOCK.
2) Some sort of feedback indicating that this particular entry is used so
we re-send arp request to perform reachability verification instead of
expiring entry. The only signal that is needed from fast path is something
like binary yes/no.
The latter is solved by the following changes:
1) introduce special r_skip_req field which is read lockless by fast path,
but updated under (new) req_mutex mutex. If this field is non-zero, then
fast path will acquire lock and set it back to 0.
2) introduce simple state machine: incomplete->reachable<->verify->deleted.
Before that we implicitely had incomplete->reachable->deleted state machine,
with V_arpt_keep between "reachable" and "deleted". Verification was performed
in runtime 5 seconds before V_arpt_keep expire.
This is changed to "change state to verify 5 seconds before V_arpt_keep,
set r_skip_req to non-zero value and check it every second". If the value
is zero - then send arp verification probe.
These changes do not introduce any signifficant control plane overhead:
typically lle callout timer would fire 1 time more each V_arpt_keep (1200s)
for used lles and up to arp_maxtries (5) for dead lles.
As a result, all packets towards "reachable" lle are handled by fast path without
acquiring lle read lock.
Additional "req_mutex" is needed because callout / arpresolve_slow() or eventhandler
might keep LLE lock for signifficant amount of time, which might not be feasible
for fast path locking (e.g. having rmlock as ether AFDATA or lltable own lock).
Differential Revision: https://reviews.freebsd.org/D3688
In case when router has a lot of multicast groups, the reply can take
several packets due to MTU limitation.
Also we have a limit IGMP_MAX_RESPONSE_BURST == 4, that limits the number
of packets we send in one shot. Then we recalculate the timer value and
schedule the remaining packets for sending.
The problem is that when we call igmp_v3_dispatch_general_query() to send
remaining packets, we queue new reply in the same mbuf queue. And when
number of packets is bigger than IGMP_MAX_RESPONSE_BURST, we get endless
reply of IGMPv3 reports.
To fix this, add the check for remaining packets in the queue.
MFC after: 1 week
Sponsored by: Yandex LLC
by filter function instead of picking into routing table details in
each consumer.
Remove now-unused rt_expunge() (eliminating last external RTF_RNH_LOCKED
user).
This simplifies future nexthops/mulitipath changes and rtrequest1_fib()
locking refactoring.
Actual changes:
Add "rt_chain" field to permit rte grouping while doing batched delete
from routing table (thus growing rte 200->208 on amd64).
Add "rti_filter" / "rti_filterdata" / "rti_spare" fields to rt_addrinfo
to pass filter function to various routing subsystems in standard way.
Convert all rt_expunge() customers to new rt_addinfo-based api and eliminate
rt_expunge().
the UDP checksum computation and signals that it was OK,
clear this bit when passing the packet to SCTP. Since the
bits indicating a valid UDP checksum and a valid SCTP
checksum are the same, the SCTP stack would assume
that also an SCTP checksum check has been performed.
MFC after: 1 week
only for read locks on pcbs. The same race can happen with write
lock semantics as well.
The race scenario:
- Two threads (1 and 2) locate pcb with writer semantics (INPLOOKUP_WLOCKPCB)
and do in_pcbref() on it.
- 1 and 2 both drop the inp hash lock.
- Another thread (3) grabs the inp hash lock. Then it runs in_pcbfree(),
which wlocks the pcb. They must happen faster than 1 or 2 come INP_WLOCK()!
- 1 and 2 congest in INP_WLOCK().
- 3 does in_pcbremlists(), drops hash lock, and runs in_pcbrele_wlocked(),
which doesn't free the pcb due to two references on it.
Then it unlocks the pcb.
- 1 (or 2) gets wlock on the pcb, runs in_pcbrele_wlocked(), which doesn't
report inp as freed, due to 2 (or 1) still helding extra reference on it.
The thread tries to do smth with a disconnected pcb and crashes.
Submitted by: emeric.poupon@stormshield.eu
Reviewed by: gleb@
MFC after: 1 week
Sponsored by: Stormshield
Tested by: Cassiano Peixoto, Stormshield
Use hhook(9) framework to achieve ability of loading and unloading
if_enc(4) kernel module. INET and INET6 code on initialization registers
two helper hooks points in the kernel. if_enc(4) module uses these helper
hook points and registers its hooks. IPSEC code uses these hhook points
to call helper hooks implemented in if_enc(4).
When the M_NOWAIT allocation fails, we recurse the if_addr_lock trying
to clean up. Reorder the cleanup after dropping the if_addr_lock. The
obvious race is already possible between if_addmulti and IF_ADDR_WLOCK
above, so it must be ok.
Submitted by: Ryan Libby <rlibby@gmail.com>
Reviewed by: jhb
Found with: M_NOWAIT failure injection testing
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D4138
new return codes of -1 were mistakenly being considered "true". Callout_stop
now returns -1 to indicate the callout had either already completed or
was not running and 0 to indicate it could not be stopped. Also update
the manual page to make it more consistent no non-zero in the callout_stop
or callout_reset descriptions.
MFC after: 1 Month with associated callout change.
Rename arp_ifinit2() into arp_announce_ifaddr().
Eliminate zeroing ifa_rtrequest: it was used for calling arp_rtrequest()
which was responsible for handling route cloning requests. It became
obsolete since r186119 (L2/L3 split).
sysctl and will always be on. The former split between default and
fast forwarding is removed by this commit while preserving the ability
to use all network stack features.
Differential Revision: https://reviews.freebsd.org/D4042
Reviewed by: ae, melifaro, olivier, rwatson
MFC after: 1 month
Sponsored by: Rubicon Communications (Netgate)
suggested by RFC 6675.
Currently differnt places in the stack tries to guess this in suboptimal ways.
The main problem is that current calculations don't take sacked bytes into
account. Sacked bytes are the bytes receiver acked via SACK option. This is
suboptimal because it assumes that network has more outstanding (unacked) bytes
than the actual value and thus sends less data by setting congestion window
lower than what's possible which in turn may cause slower recovery from losses.
As an example, one of the current calculations looks something like this:
snd_nxt - snd_fack + sackhint.sack_bytes_rexmit
New proposal from RFC 6675 is:
snd_max - snd_una - sackhint.sacked_bytes + sackhint.sack_bytes_rexmit
which takes sacked bytes into account which is a new addition to the sackhint
struct. Only thing we are missing from RFC 6675 is isLost() i.e. segment being
considered lost and thus adjusting pipe based on that which makes this
calculation a bit on conservative side.
The approach is very simple. We already process each ack with sack info in
tcp_sack_doack() and extract sack blocks/holes out of it. We'd now also track
this new variable sacked_bytes which keeps track of total sacked bytes reported.
One downside to this approach is that we may get incorrect count of sacked_bytes
if the other end decides to drop sack info in the ack because of memory pressure
or some other reasons. But in this (not very likely) case also the pipe
calculation would be conservative which is okay as opposed to being aggressive
in sending packets into the network.
Next step is to use this more accurate pipe estimation to drive congestion
window adjustments.
In collaboration with: rrs
Reviewed by: jason_eggnet dot com, rrs
MFC after: 2 weeks
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D3971
window in number of segments on fly. It is set to 10 segments by default.
Remove net.inet.tcp.experimental.initcwnd10 which is now redundant. Also remove
the parent node net.inet.tcp.experimental as it's not needed anymore and also
because it was not well thought out.
Differential Revision: https://reviews.freebsd.org/D3858
In collaboration with: lstewart
Reviewed by: gnn (prev version), rwatson, allanjude, wblock (man page)
MFC after: 2 weeks
Relnotes: yes
Sponsored by: Limelight Networks
degradation (7%) for host host TCP connections over 10Gbps links,
even when there were no secuirty policies in place. There is no
change in performance on 1Gbps network links. Testing GENERIC vs.
GENERIC-NOIPSEC vs. GENERIC with this change shows that the new
code removes any overhead introduced by having IPSEC always in the
kernel.
Differential Revision: D3993
MFC after: 1 month
Sponsored by: Rubicon Communications (Netgate)
down state.
Regression appeared in r287789, where the "prefix has no corresponding
installed route" case was forgotten. Additionally, lltable_delete_addr()
was called with incorrect byte order (default is network for lltable code).
While here, improve comments on given cases and byte order.
PR: 203573
Submitted by: phk
retransmission timeout (rto) when blackhole detection is enabled. Make
sure it only happens when the second attempt to send the same segment also fails
with rto.
Also make sure that each mtu probing stage (usually 1448 -> 1188 -> 524) follows
the same pattern and gets 2 chances (rto) before further clamping down.
Note: RFC4821 doesn't specify implementation details on how this situation
should be handled.
Differential Revision: https://reviews.freebsd.org/D3434
Reviewed by: sbruno, gnn (previous version)
MFC after: 2 weeks
Sponsored by: Limelight Networks
packets and/or state transitions from each TCP socket. That would help with
narrowing down certain problems we see in the field that are hard to reproduce
without understanding the history of how we got into a certain state. This
change provides just that.
It saves copies of the last N packets in a list in the tcpcb. When the tcpcb is
destroyed, the list is freed. I thought this was likely to be more
performance-friendly than saving copies of the tcpcb. Plus, with the packets,
you should be able to reverse-engineer what happened to the tcpcb.
To enable the feature, you will need to compile a kernel with the TCPPCAP
option. Even then, the feature defaults to being deactivated. You can activate
it by setting a positive value for the number of captured packets. You can do
that on either a global basis or on a per-socket basis (via a setsockopt call).
There is no way to get the packets out of the kernel other than using kmem or
getting a coredump. I thought that would help some of the legal/privacy concerns
regarding such a feature. However, it should be possible to add a future effort
to export them in PCAP format.
I tested this at low scale, and found that there were no mbuf leaks and the peak
mbuf usage appeared to be unchanged with and without the feature.
The main performance concern I can envision is the number of mbufs that would be
used on systems with a large number of sockets. If you save five packets per
direction per socket and have 3,000 sockets, that will consume at least 30,000
mbufs just to keep these packets. I tried to reduce the concerns associated with
this by limiting the number of clusters (not mbufs) that could be used for this
feature. Again, in my testing, that appears to work correctly.
Differential Revision: D3100
Submitted by: Jonathan Looney <jlooney at juniper dot net>
Reviewed by: gnn, hiren
unconditionally, we end up with an mbuf chain of two mbufs, which
later in in_arpreply() is rewritten from ARP request to ARP reply
and is sent out. Looks like igb(4) (at least mine, and at least
at my network) fails on such mbuf chain, so ARP reply doesn't go
out wire. Thus, make the m_pullup() call conditional, as it is
everywhere. Of course, the bug in igb(?) should be investigated,
but better first fix the head. And unconditional m_pullup() was
suboptimal, anyway.
Currently we perform crypto requests for IPSEC synchronous for most of
crypto providers (software, aesni) and only VIA padlock calls crypto
callback asynchronous. In synchronous mode it is possible, that security
policy will be removed during the processing crypto request. And crypto
callback will release the last reference to SP. Then upon return into
ipsec[46]_process_packet() IPSECREQUEST_UNLOCK() will be called to already
freed request. To prevent this we will take extra reference to SP.
PR: 201876
Sponsored by: Yandex LLC
is smaller than the current one for this connection. This is behavior
specified by RFC 1191, and this is how original BSD stack behaved, but this
was unintentionally regressed in r182851.
Reported & tested by: Richard Russo <russor whatsapp.com>
Differential Revision: D3567
Sponsored by: Nginx, Inc.
Initially function was introduced in r53541 (KAME initial commit) to
"provide hints from upper layer protocols that indicate a connection
is making "forward progress"" (quote from RFC 2461 7.3.1 Reachability
Confirmation).
However, it was converted to do nothing (e.g. just return) in r122922
(tcp_hostcache implementation) back in 2003. Some defines were moved
to tcp_var.h in r169541. Then, it was broken (for non-corner cases)
by r186119 (L2<>L3 split) in 2008 (NULL ifp in nd6_lookup). So,
right now this code is broken and has no "real" base users.
Differential Revision: https://reviews.freebsd.org/D3699
instead of old "ignore-and-return 0" in r287789. This broke arp -da /
ndp -cn behavior (they exit on rtsock command failure). Fix this by
translating LLE_IFADDR to RTM_PINNED flag, passing it to userland and
making arp/ndp ignore these entries in batched delete.
MFC after: 2 weeks
function. The change is mostly mechanical with the following exception:
Last piece of nd6_resolve_slow() was refactored: ND6_LLINFO_PERMANENT
condition was removed as always-true, explicit ND6_LLINFO_NOSTATE ->
ND6_LLINFO_INCOMPLETE state transition was removed as duplicate.
Reviewed by: ae
Sponsored by: Yandex LLC
* prepare gateway before insertion
* use RTM_CHANGE instead of explicit find/change route
* Remove fib argument from ifa_switch_loopback_route added in r264887:
if old ifp fib differes from new one, that the caller
is doing something wrong
* Make ifa_*_loopback_route call single ifa_maintain_loopback_route().
without holding afdata wlock
* convert per-af delete_address callback to global lltable_delete_entry() and
more low-level "delete this lle" per-af callback
* fix some bugs/inconsistencies in IPv4/IPv6 ifscrub procedures
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D3573
To make driver programming easier the TSO limits are changed to
reflect the values used in the BUSDMA tag a network adapter driver is
using. The TCP/IP network stack will subtract space for all linklevel
and protocol level headers and ensure that the full mbuf chain passed
to the network adapter fits within the given limits.
Implementation notes:
If a network adapter driver needs to fixup the first mbuf in order to
support VLAN tag insertion, the size of the VLAN tag should be
subtracted from the TSO limit. Else not.
Network adapters which typically inline the complete header mbuf could
technically transmit one more segment. This patch does not implement a
mechanism to recover the last segment for data transmission. It is
believed when sufficiently large mbuf clusters are used, the segment
limit will not be reached and recovering the last segment will not
have any effect.
The current TSO algorithm tries to send MTU-sized packets, where the
MTU typically is 1500 bytes, which gives 1448 bytes of TCP data
payload per packet for IPv4. That means if the TSO length limitiation
is set to 65536 bytes, there will be a data payload remainder of
(65536 - 1500) mod 1448 bytes which is equal to 324 bytes. Trying to
recover total TSO length due to inlining mbuf header data will not
have any effect, because adding or removing the ETH/IP/TCP headers
to or from 324 bytes will not cause more or less TCP payload to be
TSO'ed.
Existing network adapter limits will be updated separately.
Differential Revision: https://reviews.freebsd.org/D3458
Reviewed by: rmacklem
MFC after: 2 weeks
to provide the TCPDEBUG functionality with pure DTrace.
Reviewed by: rwatson
MFC after: 2 weeks
Sponsored by: Limelight Networks
Differential Revision: D3530
in the routine, which queues an ERROR chunk, instead on relyinh
on the callers to do so. Since one caller missed this, this actially
fixes a bug.
MFC after: 1 week
because the RSS hash may need to be recalculated.
Submitted by: Tiwei Bie <btw@mail.ustc.edu.cn>
Differential Revision: https://reviews.freebsd.org/D3564
o Unlike xor, in Jenkins hash every bit of input affects virtually
every bit of output, thus salting the hash actually works. With
xor salting only provides a false sense of security, since if
hash(x) collides with hash(y), then of course, hash(x) ^ salt
would also collide with hash(y) ^ salt. [1]
o Jenkins provides much better distribution than xor, very close to
ideal.
TCP connection setup/teardown benchmark has shown a 10% increase
with default hash size, and with bigger hashes that still provide
possibility for collisions. With enormous hash size, when dataset is
by an order of magnitude smaller than hash size, the benchmark has
shown 4% decrease in performance decrease, which is expected and
acceptable.
Noticed by: Jeffrey Knockel <jeffk cs.unm.edu> [1]
Benchmarks by: jch
Reviewed by: jch, pkelsey, delphij
Security: strengthens protection against hash collision DoS
Sponsored by: Nginx, Inc.
workaround for a callout(9) issue, it turns out it is instead the right
way to use callout in mpsafe mode without using callout_drain().
r284245 commit message:
Fix a callout race condition introduced in TCP timers callouts with r281599.
In TCP timer context, it is not enough to check callout_stop() return value
to decide if a callout is still running or not, previous callout_reset()
return values have also to be checked.
Differential Revision: https://reviews.freebsd.org/D2763
do not do what one would expect by name. Prefix them with "udp_"
to at least obviously limit the scope.
This is a non-functional change.
Reviewed by: gnn, rwatson
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D3505
timers callouts with r281599."
r281599 fixed a TCP timer race condition, but due a callout(9) bug
it also introduced another race condition workaround-ed with r284245.
The callout(9) bug being fixed with r286880, we can now revert the
workaround (r284245).
Differential Revision: https://reviews.freebsd.org/D2079 (Initial change)
Differential Revision: https://reviews.freebsd.org/D2763 (Workaround)
Differential Revision: https://reviews.freebsd.org/D3078 (Fix)
Sponsored by: Verisign, Inc.
MFC after: 2 weeks
Before that, the logic besides lle_create() was the following:
return existing if found, create if not. This behaviour was error-prone
since we had to deal with 'sudden' static<>dynamic lle changes.
This commit fixes bunch of different issues like:
- refcount leak when lle is converted to static.
Simple check case:
console 1:
while true;
do for i in `arp -an|awk '$4~/incomp/{print$2}'|tr -d '()'`;
do arp -s $i 00:22:44:66:88:00 ; arp -d $i;
done;
done
console 2:
ping -f any-dead-host-in-L2
console 3:
# watch for memory consumption:
vmstat -m | awk '$1~/lltable/{print$2}'
- possible problems in arptimer() / nd6_timer() when dropping/reacquiring
lock.
New logic explicitly handles use-or-create cases in every lla_create
user. Basically, most of the changes are purely mechanical. However,
we explicitly avoid using existing lle's for interface/static LLE records.
* While here, call lle_event handlers on all real table lle change.
* Create lltable_free_entry() calling existing per-lltable
lle_free_t callback for entry deletion
This change isolates the most common case (e.g. successful lookup)
from more complicates scenarios. It also (tries to) make code
more simple by avoiding retry: cycle.
The actual goal is to prepare code to the upcoming change that will
allow LL address retrieval without acquiring LLE lock at all.
Reviewed by: ae
Differential Revision: https://reviews.freebsd.org/D3383
separate bunch of functions. The goal is to isolate actual lle
updates to permit more fine-grained locking.
Do all lle link-level update under AFDATA wlock.
Sponsored by: Yandex LLC
This permits us having all (not fully true yet) all the info
needed in lookup process in first 64 bytes of 'struct llentry'.
struct llentry layout:
BEFORE:
[rwlock .. state .. state .. MAC ] (lle+1) [sockaddr_in[6]]
AFTER
[ in[6]_addr MAC .. state .. rwlock ]
Currently, address part of struct llentry has only 16 bytes for the key.
However, lltable does not restrict any custom lltable consumers with long
keys use the previous approach (store key at (lle+1)).
Sponsored by: Yandex LLC
* Split lltable_init() into lltable_allocate_htbl() (alloc
hash table with default callbacks) and lltable_link() (
links any lltable to the list).
* Switch from LLTBL_HASHTBL_SIZE to per-lltable hash size field.
* Move lltable setup to separate functions in in[6]_domifattach.
differences between projects/routing and HEAD.
This commit tries to keep code logic the same while changing underlying
code to use unified callbacks.
* Add llt_foreach_entry method to traverse all entries in given llt
* Add llt_dump_entry method to export particular lle entry in sysctl/rtsock
format (code is not indented properly to minimize diff). Will be fixed
in the next commits.
* Add llt_link_entry/llt_unlink_entry methods to link/unlink particular lle.
* Add llt_fill_sa_entry method to export address in the lle to sockaddr
format.
* Add llt_hash method to use in generic hash table support code.
* Add llt_free_entry method which is used in llt_prefix_free code.
* Prepare for fine-grained locking by separating lle unlink and deletion in
lltable_free() and lltable_prefix_free().
* Provide lltable_get<ifp|af>() functions to reduce direct 'struct lltable'
access by external callers.
* Remove @llt agrument from lle_free() lle callback since it was unused.
* Temporarily add L3_CADDR() macro for 'const' sockaddr typecasting.
* Switch to per-af hashing code.
* Rename LLE_FREE_LOCKED() callback from in[6]_lltable_free() to
in_[6]lltable_destroy() to avoid clashing with llt_free_entry() method.
Update description from these functions.
* Use unified lltable_free_entry() function instead of per-af one.
Reviewed by: ae
This fixes a panic during 'sysctl -a' on VIMAGE kernels.
The tcp_reass_zone variable is not VNET_DEFINE() so we can not mark it as a VNET
variable (with CTLFLAG_VNET).
* Move interface route cleanup to route.c:rt_flushifroutes()
* Convert most of "for (fibnum = 0; fibnum < rt_numfibs; fibnum++)" users
to use new rt_foreach_fib() instead of hand-rolling cycles.
* Move lle creation/deletion from lla_lookup to separate functions:
lla_lookup(LLE_CREATE) -> lla_create
lla_lookup(LLE_DELETE) -> lla_delete
lla_create now returns with LLE_EXCLUSIVE lock for lle.
* Provide typedefs for new/existing lltable callbacks.
Reviewed by: ae
Do not pass 'dst' sockaddr to ip[6]_mloopback:
- We have explicit check for AF_INET in ip_output()
- We assume ip header inside passed mbuf in ip_mloopback
- We assume ip6 header inside passed mbuf in ip6_mloopback
Avoid too strict INP_INFO_RLOCK_ASSERT checks due to
tcp_notify() being called from in6_pcbnotify().
Reported by: Larry Rosenman <ler@lerctr.org>
Submitted by: markj, jch
- The existing TCP INP_INFO lock continues to protect the global inpcb list
stability during full list traversal (e.g. tcp_pcblist()).
- A new INP_LIST lock protects inpcb list actual modifications (inp allocation
and free) and inpcb global counters.
It allows to use TCP INP_INFO_RLOCK lock in critical paths (e.g. tcp_input())
and INP_INFO_WLOCK only in occasional operations that walk all connections.
PR: 183659
Differential Revision: https://reviews.freebsd.org/D2599
Reviewed by: jhb, adrian
Tested by: adrian, nitroboost-gmail.com
Sponsored by: Verisign, Inc.
When firewalls force a reloop of packets and the caller supplied a route the reference to the route might be reduced twice creating issues.
This is especially the scenario when a packet is looped because of operation in the firewall but the new route lookup gives a down route.
Differential Revision: https://reviews.freebsd.org/D3037
Reviewed by: gnn
Approved by: gnn(mentor)
ip_output has a big chunk of code used to handle special cases with pfil consumers which also forces a reloop on it.
Gather all this code together to make it readable and properly handle the reloop cases.
Some of the issues identified:
M_IP_NEXTHOP is not handled properly in existing code.
route reference leaking is possible with in FIB number change
route flags checking is not consistent in the function
Differential Revision: https://reviews.freebsd.org/D3022
Reviewed by: gnn
Approved by: gnn(mentor)
MFC after: 4 weeks
non-inline urgent data and introduce an mbuf exhaustion attack vector
similar to FreeBSD-SA-15:15.tcp, but not requiring VNETs.
Address the issue described in FreeBSD-SA-15:15.tcp.
Reviewed by: glebius
Approved by: so
Approved by: jmallett (mentor)
Security: FreeBSD-SA-15:15.tcp
Sponsored by: Norse Corp, Inc.
ip_encap already has inspected mbuf's data, at least an IP header.
And it is safe to use mtod() and do direct access to needed fields.
Add M_ASSERTPKTHDR() to gif_encapcheck(), since the code expects that
mbuf has a packet header.
Move the code from gif_validate[46] into in[6]_gif_encapcheck(), also
remove "martian filters" checks. According to RFC 4213 it is enough to
verify that the source address is the address of the encapsulator, as
configured on the decapsulator.
Reviewed by: melifaro
Obtained from: Yandex LLC
Sponsored by: Yandex LLC
Both are used to protect access to IP addresses lists and they can be
acquired for reading several times per packet. To reduce lock contention
it is better to use rmlock here.
Reviewed by: gnn (previous version)
Obtained from: Yandex LLC
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D3149
1) We were not handling (or sending) the IN_PROGRESS case if
the other side (or our side) was not able to reset (awaiting more data).
2) We would improperly send a stream-reset when we should not. Not
waiting until the TSN had been assigned when data was inqueue.
Reviewed by: tuexen
lock on the INP before calling the tunnel protocol, else a LOR
may occur (it does with SCTP for sure). Instead we must acquire a
ref count and release the lock, taking care to allow for the case
where the UDP socket has gone away and *not* unlocking since the
refcnt decrement on the inp will do the unlock in that case.
Reviewed by: tuexen
MFC after: 3 weeks
a set of differentiated services, set IPTOS_PREC_* macros using
IPTOS_DSCP_* macro definitions.
While here, add IPTOS_DSCP_VA macro according to RFC 5865.
Differential Revision: https://reviews.freebsd.org/D3119
Reviewed by: gnn
scaling code does not use an uninitialized timestamp echo reply value
from the stack when timestamps are not enabled.
Differential Revision: https://reviews.freebsd.org/D3060
Reviewed by: hiren
Approved by: jmallett (mentor)
MFC after: 3 days
Sponsored by: Norse Corp, Inc.
apparently neither clang nor gcc complain about this.
But clang intis the var to NULL correctly while gcc on at least mips does not.
Correct the undefined behavior by initializing the variable properly.
PR: 201371
Differential Revision: https://reviews.freebsd.org/D3036
Reviewed by: gnn
Approved by: gnn(mentor)
ip_forward() does a route lookup for testing this packet can be sent to a known destination,
it also can do another route lookup if it detects that an ICMP redirect is needed,
it forgets all of this and handovers to ip_output() to do the same lookup yet again.
This optimisation just does one route lookup during the forwarding path and handovers that to be considered by ip_output().
Differential Revision: https://reviews.freebsd.org/D2964
Approved by: ae, gnn(mentor)
MFC after: 1 week
condition.
If you send a 0-length packet, but there is data is the socket buffer, and
neither the rexmt or persist timer is already set, then activate the persist
timer.
PR: 192599
Differential Revision: D2946
Submitted by: jlott at averesystems dot com
Reviewed by: jhb, jch, gnn, hiren
Tested by: jlott at averesystems dot com, jch
MFC after: 2 weeks
There is small window, when encap_detach() can free matched entry
directly after we release encapmtx. Instead of use pointer to the
matched entry, save pointers to needed variables from this entry
and use them after release mutex.
Pass argument stored in the encaptab entry to encap_fillarg(), instead
of pointer to matched entry. Also do not allocate new mbuf tag, when
argument that we plan to save in this tag is NULL.
Also make encaptab variable static.
Obtained from: Yandex LLC
Sponsored by: Yandex LLC
to be transmitted but the arp cache entry expired, which triggers an arp request
to be sent, the bpf code might want to sleep but crash the system due
to a non sleep lock held from the arp entry not released properly.
Release the lock before calling the arp request code to solve the issue
as is done on all the other code paths.
PR: 200323
Approved by: ae, gnn(mentor)
MFC after: 1 week
Sponsored by: Netgate
Differential Revision: https://reviews.freebsd.org/D2828
continue sending on the same net.
This fixes a bug where an invalid mbuf chain was constructed, if a
full size frame of control chunks should be sent and there is a
output error.
Based on a discussion with rrs@, change move to the next net. This fixes
the bug and improves the behaviour.
Thanks to Irene Ruengeler for spending a lot of time in narrowing this
problem down.
MFC after: 3 days
In TCP timer context, it is not enough to check callout_stop() return value
to decide if a callout is still running or not, previous callout_reset()
return values have also to be checked.
Differential Revision: https://reviews.freebsd.org/D2763
Reviewed by: hiren
Approved by: hiren
MFC after: 1 day
Sponsored by: Verisign, Inc.
the scope.
This fixes a problem when a client with a global address
connects to a server with a private address.
Thanks to Irene Ruengeler in helping me to find the issue.
MFC after: 3 days
years for head. However, it is continuously misused as the mpsafe argument
for callout_init(9). Deprecate the flag and clean up callout_init() calls
to make them more consistent.
Differential Revision: https://reviews.freebsd.org/D2613
Reviewed by: jhb
MFC after: 2 weeks
gif(4) interface. Add new option "ignore_source" for gif(4) interface.
When it is enabled, gif's encapcheck function requires match only for
packet's destination address.
Differential Revision: https://reviews.freebsd.org/D2004
Obtained from: Yandex LLC
MFC after: 2 weeks
Sponsored by: Yandex LLC
Although this is not important to the rest of the TCP processing
it is a conveneint way to make the DTrace state-transition probe
catch this important state change.
MFC after: 1 week
Currently we have tables identified by their names in userland
with internal kernel-assigned indices. This works the following way:
When userland wishes to communicate with kernel to add or change rule(s),
it makes indexed sorted array of table names
(internally ipfw_obj_ntlv entries), and refer to indices in that
array in rule manipulation.
Prior to committing new rule to the ruleset kernel
a) finds all referenced tables, bump their refcounts and change
values inside the opcodes to be real kernel indices
b) auto-creates all referenced but not existing tables and then
do a) for them.
Kernel does almost the same when exporting rules to userland:
prepares array of used tables in all rules in range, and
prepends it before the actual ruleset retaining actual in-kernel
indexes for that.
There is also special translation layer for legacy clients which is
able to provide 'real' indices for table names (basically doing atoi()).
While it is arguable that every subsystem really needs names instead of
numbers, there are several things that should be noted:
1) every non-singleton subsystem needs to store its runtime state
somewhere inside ipfw chain (and be able to get it fast)
2) we can't assume object numbers provided by humans will be dense.
Existing nat implementation (O(n) access and LIST inside chain) is a
good example.
Hence the following:
* Convert table-centric rewrite code to be more generic, callback-based
* Move most of the code from ip_fw_table.c to ip_fw_sockopt.c
* Provide abstract API to permit subsystems convert their objects
between userland string identifier and in-kernel index.
(See struct opcode_obj_rewrite) for more details
* Create another per-chain index (in next commit) shared among all subsystems
* Convert current NAT44 implementation to use new API, O(1) lookups,
shared index and names instead of numbers (in next commit).
Sponsored by: Yandex LLC
When we are passing mbuf to IPSec processing via ipsec[46]_process_packet(),
we hold one reference to security policy and release it just after return
from this function. But IPSec processing can be deffered and when we release
reference to security policy after ipsec[46]_process_packet(), user can
delete this security policy from SPDB. And when IPSec processing will be
done, xform's callback function will do access to already freed memory.
To fix this move KEY_FREESP() into callback function. Now IPSec code will
release reference to SP after processing will be finished.
Differential Revision: https://reviews.freebsd.org/D2324
No objections from: #network
Sponsored by: Yandex LLC
- Use the carp_sx to serialize not only CARP ioctls, but also carp_attach()
and carp_detach().
- Use cif_mtx to lock only access to those the linked list.
- These locking changes allow us to do some memory allocations with M_WAITOK
and also properly call callout_drain() in carp_destroy().
- In carp_attach() assert that ifaddr isn't attached. We always come here
with a pristine address from in[6]_control().
Reviewed by: oleg
Sponsored by: Nginx, Inc.
TCP timers:
- Add a reference from tcpcb to its inpcb
- Defer tcpcb deletion until TCP timers have finished
Differential Revision: https://reviews.freebsd.org/D2079
Submitted by: jch, Marc De La Gueronniere <mdelagueronniere@verisign.com>
Reviewed by: imp, rrs, adrian, jhb, bz
Approved by: jhb
Sponsored by: Verisign, Inc.
sequential IP ID case (e.g. ping -f), distribution fell into 8-10 buckets
out of 64. With Jenkins hash, distribution is even.
o Add random seed to the hash.
Sponsored by: Nginx, Inc.
function names have changed and comments are reformatted or added, but
there is no functional change.
Claim copyright for me and Adrian.
Sponsored by: Nginx, Inc.
of allocations in V_nipq is racy. To fix that, we would simply stop doing
book-keeping ourselves, and rely on UMA doing that. There could be a
slight overcommit due to caches, but that isn't a big deal.
o V_nipq and V_maxnipq go away.
o net.inet.ip.fragpackets is now just SYSCTL_UMA_CUR()
o net.inet.ip.maxfragpackets could have been just SYSCTL_UMA_MAX(), but
historically it has special semantics about values of 0 and -1, so
provide sysctl_maxfragpackets() to handle these special cases.
o If zone limit lowers either due to net.inet.ip.maxfragpackets or due to
kern.ipc.nmbclusters, then new function ipq_drain_tomax() goes over
buckets and frees the oldest packets until we are in the limit.
The code that (incorrectly) did that in ip_slowtimo() is removed.
o ip_reass() doesn't check any limits and calls uma_zalloc(M_NOWAIT).
If it fails, a new function ipq_reuse() is called. This function will
find the oldest packet in the currently locked bucket, and if there is
none, it will search in other buckets until success.
Sponsored by: Nginx, Inc.
free a fragment, provide two inline functions that do that for us:
ipq_drop() and ipq_timeout().
o Rename ip_free_f() to ipq_free() to match the name scheme of IP reassembly.
o Remove assertion from ipq_free(), since it requires extra argument to be
passed, but locking scheme is simple enough and function is static.
Sponsored by: Nginx, Inc.
This significantly improves performance on multi-core servers where there
is any kind of IPv4 reassembly going on.
glebius@ would like to see the locking moved to be attached to the reassembly
bucket, which would make it per-bucket + per-VNET, instead of being global.
I decided to keep it global for now as it's the minimal useful change;
if people agree / wish to migrate it to be per-bucket / per-VNET then please
do feel free to do so. I won't complain.
Thanks to Norse Corp for giving me access to much larger servers
to test this at across the 4 core boxes I have at home.
Differential Revision: https://reviews.freebsd.org/D2095
Reviewed by: glebius (initial comments incorporated into this patch)
MFC after: 2 weeks
Sponsored by: Norse Corp, Inc (hardware)
header and not only partial flags and fields. Firewalls can attach
classification tags to the outgoing mbufs which should be copied to
all the new fragments. Else only the first fragment will be let
through by the firewall. This can easily be tested by sending a large
ping packet through a firewall. It was also discovered that VLAN
related flags and fields should be copied for packets traversing
through VLANs. This is all handled by "m_dup_pkthdr()".
Regarding the MAC policy check in ip_fragment(), the tag provided by
the originating mbuf is copied instead of using the default one
provided by m_gethdr().
Tested by: Karim Fodil-Lemelin <fodillemlinkarim at gmail.com>
MFC after: 2 weeks
Sponsored by: Mellanox Technologies
PR: 7802
where we want to create a new IP datagram.
o Add support for RFC6864, which allows to set IP ID for atomic IP
datagrams to any value, to improve performance. The behaviour is
controlled by net.inet.ip.rfc6864 sysctl knob, which is enabled by
default.
o In case if we generate IP ID, use counter(9) to improve performance.
o Gather all code related to IP ID into ip_id.c.
Differential Revision: https://reviews.freebsd.org/D2177
Reviewed by: adrian, cy, rpaulo
Tested by: Emeric POUPON <emeric.poupon stormshield.eu>
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
Relnotes: yes
